Micrometric calipers.



B. NEFEDOV.

MICROMETRIC CALIPERS.

APPLICATION. FILED JUNE 21. 1916.

2 SHEETS-SHEET I.

JTW HH J K Patiented Oct. 16, 1917.

- IN VE/V TOR Ema! My? WITNESSES B. NEFEDOV.

MICROMETRIC CALIPERS.

'APPLICATION FILED JUNE 27, 19:6,

LQ43,5%5, Patented 00. 16, 1917.

2 SHEETS-SHEET 2.

WITNESSES ATTORNEYS BASIL nnrnnov, or new YORK, N. r.

MICBOMETRIG GALIPERS.

Specification of Letters Patent.

Patented Oct. 16, 1917.

Application filed June 27, 1916. Serial'No. 106,126.

To all whom it may concern:

Be it known that I, BASIL Nnrnnov, a subject of the Czar of Russia, anda resident of the city of New York, borough of Manhattan, in the countyand State of New York, have invented a new and Improved MicrometricCalipers, of which the following is a full, clear, and exactdescription.

Among the principal objects which the present invention has in view are:to provide means for disclosing with accuracy the disposition of a metalcutting tool with reference to the work upon which the cutting is to beperformed; to provide means for predetermining the proper set of a toolof the character mentioned for performing the work for which it isintended; to clearly indicate the disadjustment of a tool of thecharacter mentioned; and to avoid errors in setting tools arising fromresiliency of the tool parts or indenture of the metal being operatedupon.

Drawings.

Figure 1 is a side elevation of an instru ment of the charactermentioned showing the same disposed as in service;

Fig. 2 is a longitudinal vertical section of the same, the section beingtaken as on the median line;

Fig. 3 is an end view of the same, the registering mechanism beingomitted; j

Fig. 4 is a top plan view of the body of the instrument, the registerbeing removed;

Fig. 5 is a horizontal section of the reg ister, thesection being takenas on the line 5-5 in Fig. 2;

Fig. 6 is a top plan view of the register;

Fig. 7 is a top plan view of a modified form of the invention, partlycut away to show the attachment of the pointer to the yielding nut;

Fig. Sis a detail view showing an end fragment of the caliper blades andextensions therefor;

Fig. 9 is an edge View of a spring collar used in the present invention.

Description. I

As seen in the drawings, the instrument is provided with contact jaws 15and 16. The jaw 15 is disposed on the end of the body 17. The body 17has mounted thereon, a spirit level 18 and a caselS). The body 17 islongitudinally bored to recelve the e2;- tension bar 20, at the outerend of which is mounted the jaw 16. The bar 20 is slidably mounted inthe body 17, and is provided witha keyway into which the end of aretaining screw 21 extends. The screw 21 is suitably threaded forengagement with a tapped perforation provided therefor in the body 17,as shown best in Fig. 2 of the drawings. The bar 20 has a threaded endsection 22 engaged by an elongated nut 23. As the nut 23 is turned, thebar 20 and jaw 16 mounted thereon is projected or retracted from and tothe jaw 15. The nut 23 has a central bore, which is adapted to receivethe section 22 of the bar 20, and a lock screw 24.

At the outer end of the nut 23, a knurled collar 25 is mounted andpermanently held thereon by a screw 26. The collar 25 is provided tofacilitate the manipulation of the nut 23 for adjusting the bar 20.

Also the collar 25 is employed for setting the calipers to the proposedwork. To this end, the collar is provided with calibrated markingsforming a scale '27, the markings whereon correspond to the serviceseparation of the jaws 15 and 16. As seen in the drawings, each of thescale divisions of the calibrations indicates one-half of 1/1000 of aninch. That is to say, if the collar 25 is moved from the position shownin Fig. 4 of the drawings, to a point where the mark opposite 10 isopposite the indicating line 28, the retraction of the bar 20 is set toprovide a cut determined at the 5/1000 of an inch. It will be understoodthat the minute division thus indicated is against the abutment 30, isthe c-fiice of a spring expansion collar 31. The collar 31 rests betweena shoulder formed on a reduced portion of the nut 23 and the thread edshank 32 of a compensating nut 33. The thread on the shank of the nut 33engages an internal thread formed adjacent the outer edge of the bore inthe body 17 The end of the shank 32 presses on the collar 31, whichexpansively holds the nut 23 against the abutment 30, and the jaw 16 inits ex tended position. The nut 33 is held in its adjusted position bythe lock nut 34.

The indicating mechanism contained in the case 19, is provided to showthe accurate set of the caliper-jaws to the measurement predetermined.To this end, a pointer 35..

is visibly mounted to move over a dial 36, which is provided withcalibrations 37 having predetermined indexes. The pointer 35 isoperatively connected with the nut 23 by a transmission mechanismembodying a lever 38, from the short end of which extends a finger 39into an annular groove 40 formed in the nut 23. As seen best in Fig. 2of the drawings, the lever 38 is pivoted on a spindle 41, below the dial36, shown in Figs, 2 and 5, and lS'fllIIllSllGCl at the extremity of itslong arm with a toothed quadrant 42. The teeth of the quadrant 42 aremeshed with the pinion 43 on a spindle 44. Extended from he spindle 4Ais a toothed sector 45, the teeth whereof engage a small pinion 46 onthe pivot post 45, which extends through the dial 36 and upon which thepointer 35 is mounted.

The pointer 35 is normally held in a position removed from the 0 pointof the calibrations 37, as will be seen best in Fig. 6 of the drawings.The pointer is thus held by a flat coil spring 48.

The case 19 is closed by a protective cover $9. The cover 4L9 isprovided with a handle 50, which when pressed upon throws the cover tothe open position, such as shown in Fig. 6 of the drawings. Normally thecover is held in closed position by a spring latch 51.

Operation.

To operate the calipers shown in the drawings, the screw 24 is retractedto relieve the tension on the threads of the section 22 of the bar 20.

It will be understood that the divisions on the calibrations 29 areequal to the move ment of the bar by the nut 23 by one revolution ofsaid nut. As a rule, the calibrations 29 are provided to give what maybe termed the roughing set. The micrometric divisions are indicated inthe scale 27, on the collar 25. For example, if the work A is held in aconventional lathe on the center B of known diameter, and the finisheddiameter of the work is known: The rod 20, is adjusted in the nut 23until the scale 27 indicates the excess over the radius of the center Bto which the designed roughing cut of the work A will be carried. Thatis, if the center B has a g-inch radius and the roughing cut for theworkVA is .to be leg-inch radius, the set of the bar 20 will indicatethree-quarters of an inch from the face of the jaw 15 to the face of thejaw16. If it is then designed to produce a finish cut of 5/1000 of aninch, the collar 25 is turned until the numeral 10- on the scale 27 isopposite the line 28 on the body 17. The resultant radius of thefinished work will be 1-1; inches less 5/1000 of an inch.

Y'Vhen the instrument is set, the jaws 15 and 16 are parallel and thescrew 24 is manipulated to lock the bar 20 in position. In thiscondition of the parts, the collar 31 presses the nut 23 againsttheabutment 30. The pointer 35 on the indicator is in the pe sition shownin Fig. 6, or removed from the 0 point of the scale marked on the dial36,

When now the cutting tool C is advanced to the caliper jaw 16, as shownby dotted lines in Fig. l, the said tool moves the said 59 jaw and thebar 20 connected therewith, togethcr with the nut 23, against the finger39 of the transmission mechanism in the indicator for moving the pointer35.

The multiplication in the transmission Q5 mechanism is such that thepointer is turned one complete revolution for a relatively slightmovement of the bar According to the set of the instrument, sufiicientpressureshouldbe brought to bear on the jaw 16. to move the same untilthe pointer 35 registers with the 0 mark on the scale. I

Itis obvious that with an indicator as V sensitive as that described,the operator is at once advised of the contact ofthe cutting tool C withthe jaw 16, and is on guard to arrest the feed of the said cutting toolwhen the pointer 35 registers with the O mark on the scale.

l O O Modification.

In Fig. 7 of the drawings, is shown a modified form of the invention,The ,modification consists in substituting for the circular indicatorhaving the dial 36, an indicator having a dial 52. The dial52 has alimited scale section over which the, end of the long pointer 53 passes.The pointer 53 is substituted in the construction for the lever 38 ofthe preferred formfand has pendent finger 39 as. providedfor the lever38. The disparity-in the length of the short arm of the pointer 53 withthe long arm thereof, multiplies the ratio of the movement sufficient tomove the end of the pointer 53over a relatively wide space for arelatively smallmovement of the finger 39 and the nut 23' with which thesame is connected.

In Fig. 8 of the drawings is shownv an attachment in the form ofextension pins 54 and 55. These pins are of known length, which lengthis added to the measurement of the calibrations 29. The pins 54 and 55 1are attached to the jaws 15 and 16, by inserting threaded ends thereofinto the tapped'perforations 56 and 57 in the said jaws 15 and 16,respectively. 3

The pins 54 and 55 are particularly de- 130 ios sirable for use when thecalipers are employed for internal measurement.

1. An implement as characterized comprising a plurality of co-extensivemembers slidably connected; a plurality of contact jaws, one of saidjaws being mounted rigidly on each of said members at the adjacent endsthereof; manually operated means for spreading said jaws, said meansembodying calibrations, the initial index whereof corresponds with thetotal thickness of said jaws; yielding means normally expanding saidjaws a predetermined extent in excess of the indication of saidcalibrations; and automatic means for detecting the movement of saidjaws when compressing said yielding means, said means embodying amovementmultiplying lever the short end whereof is operatively connectedwith one of said members, the other end whereof is visible incooperation with said calibrations.

2. An implement as characterized comprising a plurality of co-extensivemembers slidably connected; a plurality of contact jaws, one of said awsbeing mounted rigidly on each of said members at the adjacent endsthereof, the total thickness of said jaws being known and the exposedsurfaces thereof being parallel; manually-operated means for spreadingsaid jaws, said means embodying calibrations, the initial index whereofcorresponds with the total thickness of said jaws; and automatic meansfor detecting the movement of said aws during the final movement fromthe manual adjustment.

3. An implement as characterized comprising a plurality of co-extensivemembers slidably connected; a plurality of contact jaws, one of saidjaws being mounted rigidly on each of said members at the adjacent endsthereof; manually operated means for spreading said jaws, said meansembodying calibrations, the initial index whereof corresponds with thetotal thickness of said jaws; yielding means normally expanding saidjaws a predetermined extent in excess of the indication of saidcalibrations; automatic means for detecting the movement of said jawswhen compressing said yielding means, said means embodying amovementmultiplying lever, the short end whereof is operativelyconnected with one of said members, the other or free end whereof isvisible;

and means for determining the extent of movement of the free end of saidlever, said means embodying calibrations, the same being divisions ofthe entire movement of said free end corresponding with the fullcontraction of said yielding means.

BASIL NEFEDOV.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

